The present invention relates to a railway system and a method for forwarding data in a railway system.
Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
Railway systems with track-bound vehicles moving on tracks are known. The tracks are typically formed of two rails, with railway signals for controlling movement of the railway cars typically arranged proximate to the tracks. Associated with the railway signals are safety devices which exchange data with each other, whereby the data are exchanged bidirectionally over both rails of the track. For data exchange, digital electrical signals in form of signal pulses, in particular electrical current pulses, are transmitted over the two electrically conducting rails. This principle is also referred to as bidirectional encoded track circuit. Each of the data consists of one or more current pulses transmitted within a cycle time, which is divided into predetermined time intervals.
The data are exchanged between corresponding to immediately adjacent safety devices in temporally alternating sequential transmit and receive cycles.
If the track is disrupted or faulty, the supervisory safety devices send a general error or maintenance message, which is forwarded in the aforedescribed manner to all safety devices of the railway system.
It would be desirable and advantageous to provide an improved system and method for transmitting additional data in addition to the data that safely control the railway signaling devices, which obviates prior art shortcomings and is able to specifically transmit the additional data without adversely affecting the transmission for the control data.